The alternative is to get one of these MiFi devices, which connect to the 3G network and operate as a Wireless Router. You can then connect wirelessly to it from a Tablet, Netbook, Laptop etc to get online.
The phone will act in a similar way to the mifi as per mgmcc. It is set up quite easily and will emit an identity of your choosing. This is seen by your tablet enabling you to connect via wifi.
I use this method with a Nexus 7. So any wifi equipment should be useable.
Be aware that not all phone providers will allow/like this. Check with your provider. One would also need to be aware of bandwidth usage.